First passage time distribution in stochastic processes with moving and static absorbing boundaries with application to biological rupture experiments
First passage time distribution in stochastic processes with moving and static absorbing boundaries with application to biological rupture experiments
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DOI：
10.1063/1.3456556
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发表时间：
2010-07-21
影响因子：
4.4
通讯作者：
Berne, B. J.
中科院分区：
文献类型：
--
作者：
Hu, Zhonghan;Cheng, Liwen;Berne, B. J.
我们开发和调查的积分方程连接的第一次穿越时间分布的随机过程中存在的吸收边界条件和相应的绿色的功能，在吸收边界的情况下。对于三个与时间无关的势中的扩散过程，得到了积分方程的解析解，这三个势以前已经用其他方法研究过。积分方程提供了一种替代的方法来解析求解三个扩散控制的反应过程。为了帮助分析生物破裂实验，我们进一步研究了含时势中扩散过程的积分方程的数值解。我们的数值计算方法，基于精确的积分方程，避免了绝热近似在以前的分析理论，是有用的拟合破裂力分布数据从单分子拉伸实验或分子动力学模拟数据，特别是在较大的拉伸速度，较大的悬臂弹簧常数，和较小的反应速率。随机模拟结果证实了我们的数值方法的有效性。我们建议结合以前的分析理论与我们的积分方程的方法来分析力诱导断裂的生物大分子的动力学。(C)2010年美国物理学会。[doi：10.1063/1.3456556]
We develop and investigate an integral equation connecting the first passage time distribution of a stochastic process in the presence of an absorbing boundary condition and the corresponding Green's function in the absence of the absorbing boundary. Analytical solutions to the integral equations are obtained for three diffusion processes in time-independent potentials which have been previously investigated by other methods. The integral equation provides an alternative way to analytically solve the three diffusion-controlled reactive processes. In order to help analyze biological rupture experiments, we further investigate the numerical solutions of the integral equation for a diffusion process in a time-dependent potential. Our numerical procedure, based on the exact integral equation, avoids the adiabatic approximation used in previous analytical theories and is useful for fitting the rupture force distribution data from single-molecule pulling experiments or molecular dynamics simulation data, especially at larger pulling speeds, larger cantilever spring constants, and smaller reaction rates. Stochastic simulation results confirm the validity of our numerical procedure. We suggest combining a previous analytical theory with our integral equation approach to analyze the kinetics of force induced rupture of biomacromolecules. (C) 2010 American Institute of Physics. [doi:10.1063/1.3456556]